Improve wp acorn compability

tests/TestCase.php

@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace AcornPlugin\Tests;
+
+use Brain\Monkey;
+use Mockery\Adapter\Phpunit\MockeryPHPUnitIntegration;
+use PHPUnit\Framework\TestCase as PhpUnitTestCase;
+
+abstract class TestCase extends PhpUnitTestCase
+{
+    // Bridges Brain\Monkey's Mockery-backed expectations into PHPUnit's
+    // assertion count, so expectation-only tests aren't reported as "risky".
+    use MockeryPHPUnitIntegration;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        Monkey\setUp();
+    }
+
+    protected function tearDown(): void
+    {
+        Monkey\tearDown();
+        parent::tearDown();
+    }
+}